| 摘要 |
<p>A self-actuating variable pich marine propeller which incorporates two or more blades (2) having cylindrical shafts (302) which are rotatably connected to a central hub (1) via cylindrical joints; the blades (2) rotate about and translate radially, relative to the hub center (Y), along the blade shaft (302), or shank axis. In operation, the blades (2) move radially outwardly from the hub center (Y) as they rotate from lower to higher pitch. The blades (2) are biased towards the lower pitch. As the propeller rotational speed increases, centrifugal forces act on the blade (2) mass creating a radially directed outward force. This radially outward force, upon reaching a sufficient magnitude, causes the blades (2) to move radially outward. A blade (2) positioning mechanism connected between each blade (2) and the hub (1) directs the blades (2) to rotate to a higher pitch angle as the blades (2) move radially outward. There is further provided a holding mechanism to retain, or hold, the blades (2) at least in one discrete pitch position; the holding mechanism is designed such that at a sharply defined combination of parameters, including rotational speed, and, optimally, hydrodynamic load on the blades (2), the blades (2) are released and permitted to move to a second pitch position.</p> |
